Recently I've added a Github open repository to apps.odoo.com and it works OK.

There is an option to add private Github repositories, giving Odoo permissions to see them including its private key, in order to publish addons, and with an option to define a price.

This is just a test for me, and to validate if it is possible to get some passive income for our work.

But private repositories on Github are not free. Since I don't know what will be going on with the validation or testing of sold addons, it would be desirable to have the option to add repositories from bitbucket for example, since you can have some private repos free of charge.

If you charge your addons with just a few euros, probably the Github recurrent price would eat this income, or worst...

Wouldn't be easy for Odoo to support Bitbucket repositories also in its Loempia implementation? The only change is an url.